package com.sky.service.impl;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.sky.constant.MessageConstant;
import com.sky.dto.UserLoginDTO;
import com.sky.entity.User;
import com.sky.exception.LoginFailedException;
import com.sky.mapper.UserMapper;
import com.sky.properties.WeChatProperties;
import com.sky.service.UserService;
import com.sky.utils.HttpClientUtil;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.time.LocalDateTime;
import java.util.HashMap;
import java.util.Map;

@Service
public class UserServiceImpl implements UserService {

    private static  final String WX_LOGIN_URL = "https://api.weixin.qq.com/sns/jscode2session";

    @Autowired
    private WeChatProperties weChatProperties;
    @Autowired
    private UserMapper userMapper;

    /**
     * 微信登录
     * @param userLoginDTO
     * @return
     */
    @Override
    public User userLogin(UserLoginDTO userLoginDTO) {
        //获取openid
        String openid = getOpenid(userLoginDTO);

        //判断openid是否为空，若空则抛出异常
        if(openid == null) {
            throw new LoginFailedException(MessageConstant.LOGIN_FAILED);
        }

        //判断当前用户是否为新用户，是则自动完成注册
        User user = userMapper.selectUser(openid);
        if(user == null) {
            user = User.builder()
                    .openid(openid)
                    .createTime(LocalDateTime.now())
                    .build();
            userMapper.insertUser(user);
        }

        return user;
    }

    /**
     * 调用微信接口服务，获取当前用户的openid
     * @param userLoginDTO
     * @return
     */
    private String getOpenid(UserLoginDTO userLoginDTO) {
        //向微信接口服务，获取当前用户的openid
        Map<String, String> claims = new HashMap<>();
        claims.put("appid", weChatProperties.getAppid());
        claims.put("secret", weChatProperties.getSecret());
        claims.put("js_code", userLoginDTO.getCode());
        claims.put("grant_type", "authorization_code");

        String result = HttpClientUtil.doGet(WX_LOGIN_URL, claims);
        JSONObject jsonObject = JSON.parseObject(result);
        String openid = jsonObject.getString("openid");
        return openid;
    }
}
